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Follow the reluctant adventures in the life of a Welsh astrophysicist sent around the world for some reason, wherein I photograph potatoes and destroy galaxies in the name of science. And don't forget about my website, www.rhysy.net

Sunday, 26 August 2012

Tuesday, 21 August 2012

Since a whole bunch of different people view my website, blog, YouTube channel and Google+ page (I could draw a Venn diagram, but I won't), here's a post to inform that particular subset who only read the blog that I've updated my website. And my YouTube channel. And my G+ page as well. Hmm. This is remarkably inefficient. Pretty soon it'll become an infinite loop of messages that I've updated the other places to tell you about the update messages...

A momentary pause leads to believe I may have unwittingly become a social networking whore, but since this has at no point involved Facebook in any way whatsoever, that's probably OK.

Anyway, this particular update mainly concerns the completion of an on-off project I've been working on for about a year - turning Blender into a FITS viewer. For the last few weeks I've decided that Paper II can gather dust while I indulge myself into making something that other people might, just possibly, actually want to use. Well, you never know.

The advantage of using Blender as a FITS viewer is that it can display full 3D-data in realtime. Having (with much help) perfected the technique of importing images mapped onto planes, and having found acceptable workarounds for all of Blender's weird, subtle nuances, I developed the script into something that may even be user-friendly. Every step* of the process can now be done within Blender via GUIs.

* Alright, ALMOST every step. If you want/need to view a subset of the data, for now you'll have to split the file with another program.

Since I already wrote about this extensively on my website (I even wrote a user guide - go, read it !) there's no point writing about it again. But by way of compensation for that subset of people who have read about this for the umpteenth time, here's another shiny video. Hopefully I'll have another 3D-data project of a tangential nature completed very soon...

The nice thing about being able to freely rotate around a cube is that no other software lets you do that, as far as I'm aware. The X-ray program dates from a time when digital watches still seemed like a pretty neat idea. It does a good job but has a hugely awkward interface, and forces you to press a "recalculate" button every time you change the view. Which is not much fun.

The latest version of ds9 is nice (in fact it's far more advanced than my code), but doesn't use the GPU, so it has to re-render every time. It does this with impressive speed, but it's nowhere near realtime. And besides, mine has a way cooler name (thanks, Gwen !).

Sunday, 19 August 2012

Some years ago I made a Project Orionvideo which is doing rather well on YouTube, and everywhere else on the internet come to that. Not so long after, I started one of several hopelessly ambitious projects, which is an absolutely normal thing for any CGI hobbyist to do. In this case the idea was to render an enormous battle between fleets of Orion-drive spaceships.

One of the original propositions of the Orion project was to use it as a warship - presumably it would initially have floated around in Earth orbit, ready to rain death upon those pesky Soviets if they started looking restless. It became known that the Russians did in fact have their own Orion program. It's just about conceivable that this could have led to giant American and Russian battleships prowling the solar system, looking for trouble. In the 1980s.

Well, it didn't, which is a very good thing. But it certainly was a fun concept to explore. In my scenario, the Cold War continues until the mid-21st century, long enough for each to develop some fancy kit, like Excalibur X-ray lasers, although sadly I never got so far as to actually render any of those, and rather more physically viable ordinary optical lasers.

In George Dyson's book (the title of the project comes from a chapter in the book), he mentions a Orion battleship model that was shown to President Kennedy, who hated the idea like any sensible human being. Having delved into the more obscure and dodgy parts of the net in the course of researching this, I found there was some doubt as to whether this really happened. In any case no images of the model exist, so I improvised my own designs.

I did some reasonably detailed calculations for this, mostly thanks to the stupendous Atomic Rockets website. Sadly I've long since lost all my notes. I worked out things like how thick the hull would have to be to withstand laser fire at different ranges, how massive the ships would need to be, and how fast they could rotate to provide gravity without making the crew get dizzy. I even worked out how much excess heat the American ship would dissipate to power its laser turrets.

I envisaged the ships being constructed in space, possibly utilising asteroid mining, so size and mass could be unlimited. Let's start with the American warship. I followed the general stereotype that the Americans would have the more advanced technology, so their primary armaments are laser cannons. Although some would have it that two would be sufficient - one at the front and one at the back - I'm not a fan of this idea. It seems better to me to employ as much redundancy as possible, so I gave it 32 laser turrets.

The way I see it, there are several advantages here. To deliver the same total power, each individual turret need only deal with a much smaller amount of energy than if only one or two were used, which I think is a sensible way to ensure greater reliability. It also means that up to 32 targets can be engaged at once, which, if the enemy is shooting a whole load of missiles at you, seems like a major win instead of having just two turrets.

The spherical shape of the American hull wasn't for any particular reason that I can remember, though it might be so that the laser turret's lines of sight are obstructed as little as possible. Following the more advanced (but possibly less reliable) American stereotype, gravity is provided to the crew by two centrifuges, counter-rotating to eliminate any gyroscopic effects. Oddly, these aren't enclosed within the main hull, making them rather vulnerable and giving it a hamburger shape.

The massive cooling fins enable a huge amount of excess energy to be dissipated, which with all those lasers is going to be necessary. These are retractable, allowing them to present a smaller target to the enemy during battle. Open-cycle cooling vents are available for emergencies if the fins are damaged.

It seems to me that while such ships could easily carry enough firepower to completely obliterate the other, this might not always be necessary. A ship with all its weapons disabled could be forced to surrender instead. So the ship is also equipped with smaller, conventional guns. These could also be used as a last-ditch defence against incoming missiles if all the laser turrets were disabled or destroyed.

Moving on, the Soviet ship has quite a different design. The pointed shape helps spread out laser-beam fire at long range, preventing the Americans from doing much damage until they're closer in. The ship has no centrifuge - gravity is provided by rotating the whole ship. This is also another way to prevent laser fire from doing much damage, if the ship is inclined toward the enemy. Since it's rather smaller than the American ship, the crew can't experience full Earth gravity, and if it's necessary to stop the rotation then they could get rather ill. However, these are trained military Cosmonauts, so I'm sure they'd cope.

The Soviet ship's weapons are mainly projectile-type. The Gauss cannons accelerate projectiles to high speed using electromagnetic coils. The other missile turrets fire conventional rocket-propelled missiles. The X-ray laser missiles are envisioned as Excalibur-style devices (even though this project probably wouldn't have worked in reality, it sounded like something fun to depict). The casaba-howitzers launch nuclear devices which explode in a tightly collimated beam.

Both of the ships can deploy armour to protect the vulnerable drive section. Of course, this won't help a jot in the event of a ship-killing weapon strike, but it ought to at least protect against debris and prevent (relatively) small arms fire from being able to cripple the ship.

A gallery of images can be found here. Below, you can watch the full 4min 45s video. But be warned. To say it hasn't aged well is being kind - but then, it wasn't finished. It ends right when the battle begins in earnest. It has a lot of problems with Blender's starfields, rudimentary animation and terrible lighting (which was partly due to technological limitations at the time). It's also far, far too long.

For the enthusiasts - and I know there are some - he's a breakdown of events as they happen. Originally there was a plan to add voice-overs, but this never happened, making things perhaps hard to interpret.

0:00 : We begin with some shots of the American fleet, en-route to the Jovian system. Perhaps the Soviets have a base there, who knows.

0:30 : The ships prepare for battle by retracting their cooling fins, causing them to heat up to maintain their energy output.

0:42 : The ships rotate and engage their Orion drives, in order to separate the fleet for battle. They travel in close formation to easily establish to the viewer that there are multiple ships.

0:55 : We see the Soviet fleet in normal cruising mode, rotating to provide internal gravity.

1:06 : The Soviet ships fire rockets to reduce their spin, preparing to use their Orion drives.

1:15 : The Soviet ships retract their cooling fins.

1:23 : A rather lengthy sequence shows the Soviet ships firing their Orion drives to separate.

2:08 : The Soviet ships are now shown to be more widely separated (though still not very far away, for narrative reasons).

2:18 : The Soviets prepare for battle by aiming their missile turrets and deploying their drive armour.

2:32 : For some reason we now see the American fleet through a telescope on a Soviet ship. I guess this is to inform the viewers that they're planning to fire on the enemy.2:40 : The Soviets fire projectiles from their Gauss cannons.

2:55 : The projectiles splinter into thousands of metal shards.

3:02 : Establishing shot of the American fleet. We see the shards from their perspective, via another cheesy telescope view.

3:14 : With thousands of high-speed metal fragments heading towards them, the Americans are forced to spend time destroying them while the Soviet fleet closes. Yes, you can see the laser beams, even though they're in a vacuum. No, this isn't something that bothers me.

3:40 : As the Americans run out of targets, the Soviets prepare to endure their laser fire. They spin-up and orient themselves at an angle to the oncoming fleet.

3:59 : The Americans now target the Soviet ships and succeed in destroying several weapon systems.

4:30 : The Soviets respond by firing a bunch of missiles. Then it ends, probably because I started my PhD and ran out of free time.

That's all folks. Although I wanted some level of realism, I wasn't concerned about getting things 100% true to life (which seems an unachievable goal for this project in any case). Sadly I'll never be able to finish this. Which means the enthusiasts will never find out who wins, and the non-enthusiasts have just wasted at least five minutes of their lives.

Thursday, 9 August 2012

Seriously. It's an awesome movie and you should watch it at once. And with one-liners like "I never expected I would be defeated by a cup of tea" I'm at a loss to explain the complete absence of internet memes. Sure, it's 5 hours long and subtitled, but so what ? It's 5 hours of AWESOME. After watching the blu-ray, I have no problem with labelling this as one of the most spectacular films of all time, right up there with Waterloo. So go out and buy it right now. That is all I have to say.

Saturday, 4 August 2012

The Olympics have reportedly cost the UK about £9 billion, which is roughly about $15 billion US. That's quite a lot of money. What it's bought us is the privilege of watching some people go running, swimming, and generally larking about for two weeks in the summer. And some urban regeneration. which I suppose is fine if you believe that what deprived inner-city areas need most are world-class sports facilities.

Now I'm all in favour of grandiose projects, but nine billions pounds for a two-week project is perhaps a tad extreme. We could have done quite a lot of other things with £9 billion. Here are a few suggestions. What's really bothering me is that it doesn't actually cost anything at all to get people to run around, or go for a swim, or even swing lumps of metal around.

1) Fully-fund the Arecibo Observatory for the next 1500 years, a period longer than the entire span of the Western Roman Empire. Now that's job security.

Say what you like, but I want my 15 centuries of science damnit !

So let's just be absolutely clear on this. The Government is forever complaining that we just don't have enough money, and have to make massive cuts to prevent an economic disaster. And then they spend enough money for people to take part in inherently free activities for two weeks that could have kept a first-rate scientific facility operational for fifteen centuries.

Bread and circuses anyone ?

2) Fund at least 260,000 post-doctoral researchers for one year. Or 2,600 post-doctoral researchers for a hundred years. Or about 250,000 PhD students for 3 years.Two hundred and sixty thousand. That's a moderately sized city. There are roughly 50 or so PhD-level scientists in Cardiff's Astronomy department, so we're talking about enough staff for five thousand institutions. Or we could get some people to throw a ball over a net.

Perhaps funding a quarter of a million students is a bad idea. Best to give it to the post-docs instead, we're much better behaved...

3) Build an Even Larger Hadron Collider. Just to really make sure. Because, you know, we could either explore the fundamental structure of matter, or put some people on trampolines.

OK, I'd take it all back if Olympic trampolining was an event entirely for pigs.

4) Build about 170 Green Bank telescopes. Of course, that'd be silly. What possible use could we find for all those elaborate facilities dotted around the landscape in unexpected places ? Building white elephants isn't what the Olympics is all about, is it ?

For context, there's only one other steerable telescope as large as the GBT in the whole world, in Germany. We could have built 170 more of them, but decided that a large puddle* and a field** would be more useful.

* Swimming pool.** Archery range.

5) Build 8 Square Kilometer Arrays. This is radio astronomy's Next Big Thing. It's going to solve all the mysteries of the Universe, and this time we really mean it. It's got a billion Euro budget and probably won't be ready for another 20 years. It ought to be pretty terrifying that the UK spent enough money in a fortnight to build eight of them.

However instead of funding a vast international project to understand the workings of the Universe, we decided to get some horses to jump over things instead. I hope the horses are well paid. Maybe if the SKA was somehow powered by jumping horses, we'd get more funding ?

6) Build 375 Allen Telescope Arrays. Last telescope in the list, I promise. This one is specifically looking for aliens. It's going to have 350 dishes when complete, but for $15 billion it could have about 131,250 of them. However, rather than wasting all that money in a boring attempt to make the greatest discovery in the history of history, we've instead opted to get some large burly men to hug each other.

7) Buy both of the UK's shiny new aircraft carriers with planes included.Sure, aircraft carriers aren't everyone's cup of tea, and maybe they're a terrible way to spend £9 billion. Still, this really ought to stop us complaining about the cost of them. On the other hand, maybe it's better we decided to throw some pointy sticks into the ground instead of shooting missiles into people.

8) Buy everyone in Britain 50 pints of beer. Or cider. Now this might not actually last as long as the Olympics for many people, but it'd be a nice gesture. A lot friendlier than those nasty aircraft carriers with all their frightful aerial weapons of death and what have you. Certainly I'd choose this option, if the alternative is nothing but sport on the TV for two weeks.

9) Build a tower of chocolate stretching more than halfway to the Moon, or nearly 4 times around the Earth.

Try as I might, I just cannot think of a good reason not to do this. Or even a bad reason not to do this. And I'm haunted by the idea that at some point in the bidding process. someone must have realised that yes, we could host the Olympic Games, but we could also give the entire country a year's supply of chocolate, but decided against it.

What a complete and utter bastard.

10) Fund the whole of science in the UK for two years. As opposed to a a sports contest that lasts two weeks. If I haven't made the point already, this should prove that science is quite cheap.

Which just goes to show that the Government is, in fact, amazing. Really, absolutely, genuinely amazing. Just not in a good way.